ISSN:0049-8246    

DOI:10.1002/xrs.1300140302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA thin‐film technique has been developed for the quantitative analysis of grindable solids such as combustion chamber and spark‐plug deposits, coal and fuel‐oil ashes, sediments and catalysts. Only 20 mg of sample are required and results are virtually independent of the matrix for all elements of atomic number 11 (Na) and heavier.Detection limits for the 25 elements so far calibrated range betweenf 0.05 and 1.0% by weight. The technique was proved using 22 certified materials, the precision being within 10% relative over much of the calibration r

ISSN:0049-8246    

DOI:10.1002/xrs.1300140303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThis review of the theory of pure element count rates measured by means of an electron microprobe analysis system with energy‐dispersive x‐ray detection defines the fundamental parameters needed for an analytical algorithm. Additionally, a presentation of these parameters by useful approximations is given. This is a basic requirement for the evaluation of theoretical expressions valid for characteristic x‐ray intensities of multielement samples. The derivation of these expressions is also given and from the results of numerous experiments it is concluded that (a) there is no systematic deviation of measured concentrations when compared with chemical analysis, (b) the quality expressed by absolute and relative errors of the analytical results is as good as that obtained by known methods that require standard samples, (c) the presented computer program, written for an HP 75C portable computer, gives the results of analysis within a calculation time of about 1 min and (d) the program is applicable to EDS and WDS both energy‐ and wavelength‐dispersive spectrometers and the range of application covers element

ISSN:0049-8246    

DOI:10.1002/xrs.1300140304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA presentation by useful approximations of fundamental parameters needed for XRF and EPMA is given. The set of fundamental parameters include: critical energy or edge energy, energy of characteristic x‐rays, edge‐jump, fluorescence yield, transition probability, mass absorption coefficient, backscatter coefficient, mean ionisation potential and atomic wei

ISSN:0049-8246    

DOI:10.1002/xrs.1300140305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractFundamental parameter methods for quantitative x‐ray fluorescence analysis require a knowledge of the spectral distributions of x‐ray tubes used for sample excitation. The theoretical models for the calculation of the spectral distributions include a number of parameters which are not known with sufficient accuracy. Also, spectral distributions have been measured for only a few x‐ray tubes operated at 45–50 kV. We have developed an algorithm for calculating x‐ray tube spectral distributions by utilizing extensive electron microprobe data obtained under various operating conditions with a Si(Li) detector. The algorithm includes the calculation of the continuum and the ratio of the characteristic line(s) to the underlying continuum intensity at the wavelength of the characteristi

ISSN:0049-8246    

DOI:10.1002/xrs.1300140306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractX‐ray K‐absorption edges of cobalt in some metallic soaps (myristate, palmitate, stearate and oleate) and their solutions in benzene have been recorded. The latter are liquid crystals. The bond length between the metal and the ligand was found to be greater in solutions than in the sol

ISSN:0049-8246    

DOI:10.1002/xrs.1300140307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA comparison has been made between light element (5

ISSN:0049-8246    

DOI:10.1002/xrs.1300140308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300140309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300140301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY